Exercise stool



FIG. 1 is a front perspective view of an exercise stool showing my new design;

FIG. 2 is a top view thereof;

FIG. 3 is a bottom view thereof;

FIG. 4 is a side view thereof,

FIG. 5 is an opposite side view thereof;

FIG. 6 is a rear view thereof; and,

FIG. 7 is a front view thereof. 

CLAIM The ornamental design for an exercise stool, as shown and described. 